In efforts to improve the overall efficiency of present day irradiation systems, a number of attempts have been made to better utilize the energies developed in the systems. For example, in X-ray irradiation systems various schemes have been developed to obtain a higher percentage of usefulness of the rays produced by X-ray tube. That is, various systems have been developed in attempts to increase the percentage of the energy converted to X-rays that is actually utilized to irradiate a product or item. Further, various other systems and methods have been explored to provide a more even distribution of the X-rays throughout the surface area of the product being irradiated.
Also, in irradiation systems using gamma-quanta irradiation sources such as cobalt-60 and cesium 137, various efforts have been made to provide more even irradiation throughout the thickness of the product being irradiated. In prior art systems, the absorbed energy distribution effective on the product being irradiated depends on various factors including the material of the target, the distance of the source to the target and on the geometry of the irradiation procedure. The present invention provides a unique system and method for obtaining a means for improving the efficiency of the desired radiation.
The present invention improves the methodology and structure of irradiation systems by utilizing, the principal that in many irradiation procedures, the irradiation provided to the product penetrates that product and there is a significant amount of photons which penetrate and exit the product.
It is an object of the present invention to effectively reuse the photons which have passed through the irradiated product and exited the product. These exiting photons are reflected back to the product to re-irradiate the product to thereby provide more efficient irradiation.
It is another object of the invention to utilize radiation exiting the product, which has heretofore been wasted, to re-irradiate the product.
It is another object of the invention to provide a more even distribution of an absorbed dose throughout the surface area of the product being irradiated and throughout the thickness of the product.
It is a further object purpose of this invention to utilize unique irradiation techniques to provide an improved irradiation system and method.
The system and method of the invention utilize a source of X-ray or gamma ray irradiation which is directed to irradiate a product. The rays penetrate the product, and significant amounts of radiation (rays) exit the product on the opposite surface of the product. A radiation reflective low Z (atomic number), high density material is provided to reflect the rays penetrating the product. The reflected rays are directed and reflected back to the product to again irradiated the product thereby utilizing the reflected rays to provide a xe2x80x9csecondaryxe2x80x9d irradiation source to effectively xe2x80x9cre-irradiatexe2x80x9d the product.
The foregoing features and advantages of the present invention will be apparent from the following more particular description of the invention. The accompanying drawings, listed herein below, are useful in explaining the invention.